The present invention relates to a process for improving properties of a synthetic resin powder, and more particularly to a process for improving properties of a synthetic resin powder which comprises subjecting a latex of a graft-copolymer whose back bone is a rubber to coagulation and adding a lubricant to the obtained graft-copolymer, thereby obtaining a synthetic resin powder having excellent properties.
Various studies have hitherto been made for improving properties to be required as a powder such as fluidity and blocking resistance of a synthetic resin powder. There are, for instance, a method in which a latex of a copolymer is solidified in a gaseous phase as described in Japanese Unexamined Patent Publication No. 59929/1982, a method in which a latex of a copolymer is spray-dried, a method in which a latex of a copolymer is dispersed in a specific solvent in the state of a sphere and coagulation of the copolymer is carried out, and the like.
However, the known methods have insufficient effects for the improvement of properties of a synthetic resin powder. So, there has not yet been obtained a synthetic resin powder having the fluidity and blocking resistance to automatically weigh the resin powder and to prevent the tendency of the powder to increase in volume during mass in transport. The present inventors have considered that improvement of the properties of a synthetic resin powder is indispensable for applying to the automatic weighing and the tendency to grow larger in transport.
An object of the present invention is to provide a process for improving properties of a synthetic resin powder, thereby obtaining a resin powder sufficiently applicable to the above-mentioned requirements.
This and other objects of the present invention will become apparent from the following description.